1. Field of the Disclosure
The disclosure generally relates to the formation of an acyloxy carboxylic acid compound by reaction of a hydroxy acid compound with a carboxylic acid (e.g., 2-acetoxy propanoic acid formed from lactic acid and acetic acid). The reaction can be performed in a reactive distillation column to provide improved reactant conversion and product yield.
2. Brief Description of Related Technology
Filachione et al. U.S. Pat. No. 2,399,595 discloses a process for manufacturing acyloxy carboxylic acids. Batch reaction of a hydroxy carboxylic acid with a carboxylic acid in the presence of a catalyst and an entraining agent forms the acyloxy carboxylic acid product. The exemplified batch processes result in product yields ranging from about 50% to about 80%.
Lilga et al. U.S. Pat. No. 6,992,209 discloses methods for forming α-,β-unsaturated acids and esters from a corresponding α-acyloxy carboxylic acid. Reaction of an α-hydroxy carboxylic acid or ester with a carboxylic acid in the presence of a catalyst forms the α-acyloxy carboxylic acid. The exemplified batch processes result in combined product and product derivative yields ranging from about 90% to about 95% using a large excess of the carboxylic acid.